Prevalence of pharmacogenomic variants in 100 pharmacogenes among Southeast Asian populations under the collaboration of the Southeast Asian ...

 
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Prevalence of pharmacogenomic variants in 100 pharmacogenes among Southeast Asian populations under the collaboration of the Southeast Asian ...
Runcharoen et al. Human Genome Variation (2021)8:7
                                    https://doi.org/10.1038/s41439-021-00135-z                                                                                                Human Genome Variation

                                     DATA REPORT                                                                                                                                                Open Access

                                    Prevalence of pharmacogenomic variants in 100
                                    pharmacogenes among Southeast Asian
                                    populations under the collaboration of the
                                    Southeast Asian Pharmacogenomics Research
                                    Network (SEAPharm)
                                    Chakkaphan Runcharoen1, Koya Fukunaga2, Insee Sensorn1, Nareenart Iemwimangsa1, Sommon Klumsathian1, Hang
                                    Tong3, Nam Sy Vo4, Ly Le3,4, Tin Maung Hlaing5, Myo Thant6, Shamsul Mohd Zain7, Zahurin Mohamed7, Yuh-Fen
                                    Pung8, Francis Capule9, Jose Nevado Jr.10, Catherine Lynn Silao10,11, Zeina N. Al-Mahayri 12, Bassam R. Ali13, Rika
                                    Yuliwulandari 14,15, Kinasih Prayuni15, Hilyatuz Zahroh15, Dzul Azri Mohamed Noor16, Phonepadith Xangsayarath17,
                                    Dalouny Xayavong17, Sengchanh Kounnavong18, Somphou Sayasone18, Zoe Kordou19, Ioannis Liopetas19, Athina
                                    Tsikrika19, Evangelia-Eirini Tsermpini 19, Maria Koromina19, Christina Mitropoulou20, George P. Patrinos12,19, Aumpika
                                    Kesornsit21, Angkana Charoenyingwattana1, Sukanya Wattanapokayakit22, Surakameth Mahasirimongkol22, Taisei
                                    Mushiroda2 and Wasun Chantratita1
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                                      Abstract
                                      Pharmacogenomics can enhance the outcome of treatment by adopting pharmacogenomic testing to maximize drug
                                      efficacy and lower the risk of serious adverse events. Next-generation sequencing (NGS) is a cost-effective technology
                                      for genotyping several pharmacogenomic loci at once, thereby increasing publicly available data. A panel of 100
                                      pharmacogenes among Southeast Asian (SEA) populations was resequenced using the NGS platform under the
                                      collaboration of the Southeast Asian Pharmacogenomics Research Network (SEAPharm). Here, we present the
                                      frequencies of pharmacogenomic variants and the comparison of these pharmacogenomic variants among different
                                      SEA populations and other populations used as controls. We investigated the different types of pharmacogenomic
                                      variants, especially those that may have a functional impact. Our results provide substantial genetic variations at 100
                                      pharmacogenomic loci among SEA populations that may contribute to interpopulation variability in drug response
                                      phenotypes. Correspondingly, this study provides basic information for further pharmacogenomic investigations in
                                      SEA populations.

                                                                                                                                          Pharmacogenomics is the study of how an individual’s
                                                                                                                                        genomic profile influences their response to drug treat-
                                                                                                                                        ments. This has emerged as a potential tool to optimize
                                    Correspondence: Taisei Mushiroda (mushiroda@riken.jp) or
                                                                                                                                        medications and reduce adverse drug events1. Genotyping
                                    Wasun Chantratita (wasun.cha@mahidol.ac.th)
                                    1
                                     Center for Medical Genomics, Faculty of Medicine Ramathibodi Hospital,                             data from next-generation sequencing (NGS) technolo-
                                    Mahidol University, Bangkok, Thailand
                                    2
                                                                                                                                        gies are increasing in international public databases,
                                     Laboratory for Pharmacogenomics, RIKEN Center for Integrative Medical
                                                                                                                                        thereby enabling new advances in pharmacogenomic
                                    Sciences, Yokohama, Japan
                                    Full list of author information is available at the end of the article                              research. Implementation guidelines of the data are now
                                    These authors contributed equally: Chakkaphan Runcharoen, Koya Fukunaga

                                    © The Author(s) 2021
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                                    Official journal of the Japan Society of Human Genetics
Runcharoen et al. Human Genome Variation (2021)8:7                                                            Page 2 of 6

available from organizations such as the Clinical Phar-      the variant calling processes, 3527 variants were called
macogenetics Implementation Consortium (CPIC)2.              and passed for VQSR processes. In total, 306 variants
  The Southeast Asian Pharmacogenomics Research              (excluding multiallelic variants) were jointly observed in
Network (SEAPharm) was founded in 2012. SEAPharm             the SEA populations (Supplementary Table 8). To quan-
aims to be the regional pharmacogenomics (PGx) network       tify the differences in frequencies between this dataset and
to strengthen the knowledge of PGx research and its          the public genome dataset, the frequencies of the 306
implementation approaches in SEA countries3. In 2018,        variants identified in this dataset and in the East Asian
the annual SEAPharm meeting approved an expanded             (EAS) control datasets from the Genome Aggregation
research collaboration under the project entitled “Re-       Database (gnomAD v.2.1.1) were compared using scatter
sequencing Project of 1,000 Southeast Asian Individuals      plots and correlation coefficient analysis (Fig. 1a). The
Using the 100 Pharmacogene - Next Generation                 results revealed concordance between the allelic fre-
Sequencing Panel” using the NGS platform. Nine coun-         quencies in this dataset (in all the SEA populations) and in
tries participated in this project: seven countries from     the EAS dataset from gnomAD. Considering the corre-
Southeast Asia (Indonesia, Laos, Malaysia, Myanmar,          lation coefficient R, there was a trend of high correlations
Philippines, Thailand, and Vietnam) and one each from        in the frequencies of variants in the Thailand, Vietnam,
Europe (Greece) and Western Asia (United Arab                and EAS datasets. To investigate the proportion of the
Emirates; UAE).                                              total pharmacogenomic variants contained in SEA
  The 100 PKSeq panel is composed of 37 drug trans-          populations, pairwise Fst statistics of the seven SEA
porter genes, 30 cytochrome P450 (CYP) enzyme-               countries, UAE, and Greece were performed. The results
encoded genes, 10 uridine diphosphate glucuronosyl-          indicated that the SEA populations had modest genetic
transferase (UGT) genes, 5 flavin-containing mono-            similarity (pairwise Fst value
Runcharoen et al. Human Genome Variation (2021)8:7                                                                                 Page 3 of 6

  Fig. 1 Scatter plot and correlation coefficient of this dataset and EAS datasets from gnomAD and pairwise weighted Fst statistics between
  SEA populations. a Frequencies of the 306 pharmacogenomic variants between this dataset and East Asian (EAS) datasets from gnomAD. AF Allele
  frequency. b Pairwise weighted Fst statistics between SEA, UAE, and Greek populations.

Myanmar residing in the USA demonstrated that the                         varied among subpopulations (i.e., Shanghai (MAF =
MAF of rs1065852 was higher in this population (A)                        0.484), Xi’an (MAF = 0.407), Shenyang (MAF = 0.467),
(MAF = 0.36) than in the American (AMR, MAF = 0.15)                       and Shantou (MAF = 0.288))12. In addition, this variant
and South Asian (SAS, MAF = 0.16) populations and                         has been reported as a major allele in Taiwanese13. The
slightly lower than that in the EAS population10.                         LD plot of CYP2D6 in the population revealed that five
rs1065852 (A) is recognized as a key mutation in                          SNPs (rs1135840, rs16947, rs1058164, rs1081003, and
CYP2D6*10. In Malaysia, the allelic frequencies of                        rs1065852) in the Philippinean, Thailand, and Vietnamese
CYP2D6*10 differed between the Chinese-Malaysians,                        populations and three SNPs (rs1058164, rs1081003, and
Malay-Malaysians, and Indian-Malaysians11. Only the                       rs1065852) in the Laos population were in very high LD
MAF of the CYP2D6*10 allele was noted in the Indian-                      (Supplementary Fig. 13). These SNPs are key mutations in
Malaysians (MAF = 0.214). However, the frequencies of                     CYP2D6*10A and CYP2D6*54 and cause a decrease in
rs1065852 (A) are not represented for CYP2D6 copy                         enzyme activity. As previously described, CYP2D6*10 is
number variation (CNV)-variable haplotypes such as                        responsible for the intermediate metabolizer status in SEA
CYP2D6*36. The frequency of rs1081003 (A) was 0.412                       populations. However, the prevalence of these alleles
among the Chinese population. The frequencies also                        is low in Malay-Singaporeans, Chinese-Singaporeans,

Official journal of the Japan Society of Human Genetics
Runcharoen et al. Human Genome Variation (2021)8:7                                                                        Page 4 of 6

                                                                       MAFs of rs2291075 (T) are 0.400 and 0.470 in the Bur-
                                                                       mese and Vietnamese populations. In Singapore, the fre-
                                                                       quencies of rs2291075 (T) vary between subpopulations
                                                                       (CHS, INS, and MAS); nonetheless, the MAF was
                                                                       observed only in INS (MAF = 0.031)19. Moreover,
                                                                       rs2291075 (T) was previously described as a MAF in
                                                                       Korean (MAF = 0.436) and Japanese (MAF = 0.367)
                                                                       populations. In contrast, this variant was found to be a
                                                                       major allele among the Chinese population20. rs2291075,
                                                                       which encodes the transporter OATP1B1, is in strong LD
                                                                       with rs2306283 and rs4149056. Inheritance of variability
                                                                       in the transporter OATP1B1 may influence the effec-
                                                                       tiveness of acute myeloid leukemia (AML) therapy
                                                                       because this transporter is responsible for the systemic
                                                                       pharmacokinetics of several drugs used in AML
                                                                       treatment21.
                                                                          Although the SEA populations seem to have genetic
                                                                       similarities, differences in allele frequencies between the
                                                                       populations were observed. A previous large-scale study
                                                                       of pharmacogenomic biomarkers in 18 European popu-
                                                                       lations demonstrated allele frequency differences in the
                                                                       interpopulations22. Additionally, the genotyping of CYP
                                                                       genes across Native American and Ibero-American
                                                                       populations revealed differences within Native Amer-
                                                                       icans23. These findings support that ethnicity affects dif-
                                                                       ferences in drug response and/or toxicity. To support the
                                                                       need for personalized precision medicine, the interethnic
  Fig. 2 Comparison of the frequencies of major genes responsible      differences of SEA populations should be taken into
  for drug metabolism enzymes and transporters in the SEA              consideration to reliably predict drug safety and efficacy at
  populations. a) Frequencies of pharmacogenomic variants of CYP2C9,   the population level.
  CYP2C19, CYP2D6, and CYP3A4. b) Frequencies of pharmacogenomic
  variants of ABCB1, ABCG2, SLC22A2, SLC22A6, SLC22A8, SLCO1B3 and
                                                                          We further investigated the functional impact of these
  SLCO1B3. AF, Allele frequency.                                       pharmacogenomic variants, including deleterious mis-
                                                                       sense mutations and loss-of-function mutations, among
                                                                       the SEA populations. Deleterious missense mutations
Indian-Malaysians, and Indian-Singaporeans14. Addition-                were determined by multiple algorithms from a database
ally, two variants of the drug transporter genes, namely,              for the functional predictions of nonsynonymous SNPs
rs1128503 (G) and rs2291075 (T) of ABCB1 and                           (dbNSFP v3.0) via VarSeq (Golden Helix, Inc., Bozeman,
SLCO1B1, respectively, differed in the observed allele                 MT, USA, www.goldenhelix.com). Considering the func-
frequencies between populations (Fig. 2b). Interestingly,              tional impacts of the variants (i.e., major allele frequencies
some ABCB1 variants seem to be more frequent in Fili-                  and MAFs), there was a trend of higher proportions of
pinos, such as rs1045642 (G), with an allele frequency of              deleterious missense and loss-of-function mutations in
0.71. However, ABCB1 rs1128503 (G), a minor allele in                  the MAF variants (Supplementary Fig. 14). In particular,
other SEA populations, was found to be a major allele                  rare variants (MAF < 0.01) accounted for the highest
among Filipinos. Previously, rs1128503 (G) was docu-                   proportions of deleterious missense and loss-of-function
mented as a major allele among Chinese and Singaporean                 mutations. Whole-genome sequencing of Malaysians
populations; however, rs1128503 (G) was found to be a                  revealed 693 variants of 8550 predicted deleterious var-
minor allele in the Indonesian population15,16. rs1128503,             iants in 437 pharmacogenomic genes involved in drug
rs2032582, and rs1045642 are the most common SNPs in                   metabolism. Almost seventy percent (70%) of the variants
the coding region of ABCB1; moreover, these SNPs are in                were rare alleles24. The investigation of variants in 12 CYP
strong LD17. The homozygous variants for one of three                  genes revealed that the majority of variants are remark-
ABCB1 variants, rs1128503 (T), rs2032582 (T, A), and                   ably rare in both African-American and European-
rs1045642 (T), are associated with significantly high                   American ancestries25. Additionally, a large proportion
short-term remission rates after tacrolimus treatment in               of rare alleles with the potential to impact drug metabo-
steroid-refractory ulcerative colitis (UC) patients18. The             lism has been documented in Slovenian and Latino

Official journal of the Japan Society of Human Genetics
Runcharoen et al. Human Genome Variation (2021)8:7                                                                                                          Page 5 of 6

populations26,27. This is also supported by the investiga-                           Publisher’s note
tion of individual variants by sequencing drug target                                Springer Nature remains neutral with regard to jurisdictional claims in
                                                                                     published maps and institutional affiliations.
genes, which demonstrated that rare variants are abun-
dant in humans, and many have potentially relevant                                   Supplementary information The online version contains supplementary
effects on drug metabolism25,28,29. Rare variants of phar-                           material available at https://doi.org/10.1038/s41439-021-00135-z.
macogenes are significantly associated with variations that
                                                                                     Received: 24 July 2020 Revised: 24 November 2020 Accepted: 28
contribute to a significant portion of the unexplained                                November 2020
interindividual differences in drug metabolism pheno-
types, thereby causing functional alterations28,30.
  In conclusion, this report presents the data on the fre-
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